Re: ATM Eyepiece focal distances

[andydtg@alpha1.phoenix.net]

Spencer Roedder wrote:
>
>My question is, does anyone have actual values of two parameters for
>various real eyepieces that are out there: the distance from the focal
>plane to the shoulder of the eyepiece, and (less important) the
>corresponding distance (+ or -) from FP to inside end of eyepiece?
>(The latter number I see as being useful to (a) avoid impinging on
>the incoming light path in the case of a _very_ low profile focuser,
>and (b) when considering making parfocalizing "collars" for a set of
>eyepieces.)

I have fairly accurate drawings in AutoCAD of most of Tele-vue's
Nagler & WF eyepieces, showing the relationship between the
telescope focal plane, eyepiece shoulder, and front of eyepiece
barrel. These dimensions were obtained by testing these eyepieces
in a telescope. I can send a .dwg or .dxf file to anyone wanting
this info, or a paper copy by snail mail.

Andy Saulietis / DTG Alt-Az-Fp Drive Systems
12617 Harriet Ln
Santa Fe, TX 77510 USA
409-925-8854 Voice/Fax